1. Field of the Invention
This invention relates to methods and apparatus for modifying fabrics to obtain varied effects. More particularly, the invention is concerned with treating fabrics to change the feel (hand), appearance or material constitution of the fabrics.
2. Description of the related art including information disclosed under Sections 1.97-1.99.
Many kinds of treatments or modifications of fabrics have been practiced for a long time. Fabrics at different stages of manufacture have been treated to alter existing characteristics and obtain a fabric which is more useful or more attractive to the ultimate user of an article made from such fabric. Known practices include modifying fabrics by laundering, beating, shearing fibers, selectively heating portions, selectively dyeing or bleaching, ironing, brushing or abrading, pressing with heated drums or patterned rolls and treating with jets of hot fluids. Techniques such as laundering, brushing or abrading with sandpaper have been employed to obtain the effect of a worn or laundered appearance, which is attractive to the user of the article. Methods involving such techniques as shearing fibers, treating with hot fluid jets or using heated drums or patterned rolls are employed to create designs or sculptured effects particularly on pile fabrics. By means of these known techniques, fibers in the pile fabrics are selectively cut, crushed or through heating especially of synthetic fibers, melted or softened so that a patterned or sculptured effect is formed in the treated locations which are altered in contrast with portions of the fabric where the fibers are untreated. Known techniques involving dyeing or bleaching have been used to produce design effects or patterns, and abrading by sanding methods have been employed to create textured or napped surfaces.
For example, in order to obtain the desired worn or laundered effect especially on denim fabric, several techniques are employed and others have been attempted. The manufacture of denim garments often includes washing the garments in various ways including regular mechnical laundering, a chlorine bleach washing, enzyme washing or stonewashing. In the latter technique, the fabric in the form of garments is washed in the presence of pumice stones in a mechanical laundering system including chlorine bleaching. By removing sizing and dye, garments are obtained which are softer and have a faded or worn look. It is also known to treat the fabric prior to the manufacturing of the garment, though commercially impractical. Fabrics have been subjected to mill washing with agitation, to remove starch. Brushing or sanding methods have been proposed to remove surface starch and surface dye but such methods have been considered to unduly weaken the fabric and are limited because they affect only the surface of the fabric.
Lesley U.S. Pat. No. 3,952,555 issued on Apr. 27, 1976 describes providing warp knit denim fabrics having the appearance of woven denim fabrics, by selectively dyeing the knit yarns. The surface of the knit fabric is sanded by contact with a machine having a sanding roll, or is napped with a napping machine having pile rolls, to enhance the denim effect.
In Mazzone et al U.S. Pat. No. 3,613,186 granted on Oct. 19, 1971, jets of hot fluid such as hot air are directed at fabric having a thermoplastic surface to , soften and sculpture the threads. Hergert U.S. Pat. No. 3,785,016 issued Jan. 15, 1974 contacts a pile fabric with a pattern roll which produces surface patterns by different treatment thermal sculpturing and ironing. Ruppe U.S. Pat. No. 3,939,536 issued on Feb. 24, 1976 discloses apparatus which compresses pile fabrics between to provide a crushed appearance. Thal et al U.S. Pat. No. 3,256,581 issued on June 21, 1966 discloses apparatus for treating pile fabrics in which a plurality of fluid discharge nozzles are moved relative to a pile fabric and also relative to each other, to impart a desired design in the pile fabric. It is disclosed that the application of jets of heated fluids to the face of pile fabrics affects the fibers in a way to cause patterns or designs.
However, the known methods for treating fabrics have a number of disadvantages. Such methods are generally capable of producing only a single specific type of effect or modification of the fabric, or a very limited range of such effects. The known techniques are usually useful only with respect to a limited class of fabrics. Installation of expensive equipment is required to carry out many such methods, and the equipment cannot be readily modified to produce any wide range of different types of effects on varying types of fabrics. Furthermore, some of the methods as noted above tend to weaken or otherwise degrade the fabric to an unacceptable extent.